For example, in a semiconductor device manufacturing process, the diameter of a semiconductor substrate such as, for example, a silicon wafer or a compound semiconductor wafer has recently been increased, and also, the thickness of the semiconductor substrate has recently been decreased. A thin large-diameter semiconductor substrate may warp or crack when it is conveyed or polished. Accordingly, the semiconductor substrate is reinforced by bonding a supporting substrate thereto, and conveyed or polished, and then, the supporting substrate is separated from the semiconductor substrate. See, e.g., Japanese Laid-Open Patent Publication No. 2012-146756.
Japanese Laid-Open Patent Publication No. 2012-146756 discloses a peeling system in which a peeling device configured to separate the supporting substrate from the semiconductor substrate, a cleaning device configured to clean bonded surfaces of the semiconductor substrate and the supporting substrate after separation, an inversion device configured to invert the front and rear surfaces of the separated semiconductor substrate, and a rear surface cleaning device configured to clean a rear surface (a non-bonded surface) of the semiconductor substrate are integrally incorporated.